#include <iostream>
#include <thread>
#include <queue>
#include <mutex>
#include <condition_variable>
#include <vector>
#include <functional>
using namespace std;
class ThreadPool{
vector<thread> threads;
queue<function<void()>> tasks;
condition_variable cond;
mutex m;
bool exited = false;
public:
ThreadPool(int num){
auto routine = [this](){
while(true){
unique_lock<mutex> lock(m);
while(tasks.empty() && !exited) cond.wait(lock);
if(exited) break;
auto func = tasks.front();
tasks.pop();
lock.unlock();
func();
}
};
for(int i=0;i<num;++i){
// thread t(routine);
// threads.emplace_back(move(t));
// threads.emplace_back(thread(routine));
threads.emplace_back(thread{routine});
}
}
~ThreadPool(){
exited = true;
cond.notify_all();
for(auto& thread:threads){
thread.join();
}
}
ThreadPool(const ThreadPool&) = default;
ThreadPool& operator=(const ThreadPool&) = default;
void AddTask(function<void()> func){
lock_guard<mutex> guard(m);
tasks.push(func);
cond.notify_one();
// signal
}
};
int main(){
mutex m;
auto test = [&m](){
this_thread::sleep_for(2s);
lock_guard<mutex> guard(m);
cout << this_thread::get_id() << " do something..." << endl;
};
ThreadPool pool(5);
for(int i=0;i<15;++i){
pool.AddTask(test);
}
this_thread::sleep_for(10s);
}
